It is well known that an iminothiazoline derivative of the general formula: ##STR3## wherein R.sup.1 is halogen or halo(lower)alkyl, halo(lower)alkoxy or halo(lower)alkylthio; R.sup.2 is hydrogen or halogen; and R.sup.4 is hydrogen or lower alkyl, is useful as an intermediate for production of herbicidal compounds (see, e.g., European Patent Publication No. 446802).